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<title>小学生口算系统</title>
<h1 align="center" ><font  color="#4169E1">小学生口算系统(家长老师)</font></h1>
<p align="center">请按照依次输入最大计算数，出题量，运算规则</p>
<p align="center">例如:20,20,+</p>
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